Apparatus for dry distillation



UNITED STATES PATENT OFFICE...

NOEL STATHAM, OF BOOIN'TON, NEW JERSEY, ASSIGNOR T0 WEST VIRGINIA PULP AND FABER COMPANY, OF NEW YORK, N. Y., A COMORATION OF DELAWARE.

APPARATUS FOR DRY DIS'IILLATION.

Spegifi'cation of Letters Patent.

Patented Apr. 4, 1922.

Application filed Kovember 15, 1915, Serial No. 61,713. Renewed June 30, 1921. Serial No; 481,707.

is a specification, taken \inconnection with the accompanying drawing, which forms part of the same.

This invention relates especially to ap paratus for the dry distillation of acetatesof calcium, sodium or the like or of mate rials containing the same by which the charge may be uniformly and gradually heated while being continuously and thoroughly agitated within a rotating retort under such conditions as to secure the most favorable heat treatment and minimize danger of injurious local overheating and loss of the desirable volatile products.- A In the accompanying drawing showing in a somewhat diagrammatic way an illustrative form of apparatus which may be used in connection with this invention,

Fig. 1 is a vertical section taken substantially along the line 1-1 of Fig. 2; and

Fig. 2 is a transverse vertical section taken substantially along the line 2-2 of Fig. 1. This apparatus may comprise a rotating metallic retort 5 which may as indicatedbe substantially cylindrical and may with advantage be mounted horizontally by any suitable means. As shown the retort is provided with hollow axial trunnions 2 mounted in suitable bearings, such as 3 and provided with one or more rotating gears or wheels, such as 4, by which the retortmay be rotated at any desired speed from time to time. The retort may be heated by any suitable heatingarrangement preferably supplying heat thereto in a substantially uniform man- I ner throughout the length of the retort and this may be effectively done by mounting the retort in an enclosed annular heating chamber, such as 24, formed within the brick work or other housing 1 and supplying heat to'the retort by suitable furnaces or heaters preferably provided with a series of regulable inlet ports 14 communicating with the chamber at various points along the same and controlled by dampers, such as 20, so that the supply of heat at any point can be correspondingly regulated. If desired a suitable I bridge or partition 28 may be.

formed in this chamber so as to guide the "hot gases which may be supplied below the ascending side of the retort under the same and up around the other side of the retort so as to be finally discharged through suitable outlet ports 15 which may with advantage be arranged in staggered relation to the inlet ports and be provided with similar regulating dampers 19 and communicate with a dlscharge flue l7 and chimney 18.

Any convenient fuel may be used to supply this heat and as indicated one or more suitable heating injectors such as an oil or natural gas injector 33 may be used in this connection and mounted in cooperation with the injecting opening 32 of a suitable'combustion chamber, such as 21, so as to insure the proper combustion of the fuel before supplying the flame or hot gases to the heating chamber around the retort.

Y The retort which may be welded or other wise formed of plates of steel so as to give the desired rigidity and strength and also a maximum of heat conductivity under operating conditions, may be provided with one or more suitable charging man-holes 22 which may be used for charging" the retort when the cover 27 is removed, from the corresponding charging opening or hopper 16 above. These chargingman-holes may also be used to dischargethe retort by being opened and rotating the retort and allowing the discharged material to escape through tures or discharge devices in the housing below. In this connection it is of advantage to have a movable discharge sleeve such as 11, mounted in the housing and adapted to closely embrace the discharge valve under discharging conditions and for this purpose the discharge sleeve or pipe 11 may be bodily movable in the housing and may be elevated at the proper time by the lifting gear 12 comprising a gear wheel and rack as indicated so as t bring this sleeve derstood that the housing is so formed as to allow the retort and these auxiliary devices thereon to rotate freely and for this purpose the partition 28 may be formed with.

suitable recesses to accommodate the discharge valve and other projecting parts, such as the charging man-holes. Suitable thermometer cups, such as 26, may also be arranged at intervals along the retort shell so as to determine its temperature at various points and assist in the regulation of the heat supply so as to ensure the proper control ofthe heatingoperation.

A' charge of crude calcium acetate or acetate of lime 23 or material containing the same may be run into the retort which may in some cases have as much as half or two-thirds its capacity filled-with this charge and then when the manholes are closed the slow rotation of the retort is commenced and the heat is supplied thereto so that it is quickly and uniformly transmitted through the metal shell and directly supplied thereby to the charge of material which is tumbled over and over by the rotation of the retort so that the rising upper part of the charge to which the heat has been directly transmitted is distributed down the inclined bank of material 23 as indicated in Fig. 2 and danger of local overheating practically prevented so long as the heat is maintained fairly uniformly distributed longitudinally of the retort. As indicated the inlet pipe 6 for supplying superheated steam or the like during the distillation may with advantage be provided with a raised inner end so as not to interfere with a large charge of material and escape of material through the hollow trunnion of the retort may be prevented by a suitable baffle 29 in which the pipe may be removably or permanently mounted. The outlet or vapor pipe 7 may have a similar raised inner end as indicated and maybe supported in a similar baflle 29, while its outer end asses through a union or packing 9 provided in the end of the trunnion so as to make a tight joint therewith while allow- 'ing the volatile material to be led away from the retort to the separating and con densing devices. In effecting the dry distillation of a charge of acetate of lime, for instance, the charge which is preferably continuously agitated by the slow rotation of the retort is brought as rapidly as convenient to a heat of about 300 degrees centigrade or mor at which the acetone begins to be given 0 V and as soon as this temperature isreached the acetone vapor is evolved in large quantities and continues to be produced for several hours, the temperature during this period being preferably kept substantially uniform-so as to prevent overheating of any of the material and theconsequent undesirable splitting up of the acetone or conversion of the acetate into relatively worthless products. The supplying of superheated steam seems to be beneficial during this stage of the distillation which may be continued until the acetone vapor ceases to be given off in-such abundant quantities and then it is generally desirable especially with some forms of crude acetate material to raise the temperature considerably and recover any more difiicultly volatile components which can be distilled from the charge at higher temperatures. The spent material may be readily discharged from the still and another charge supplied thereto practically without hand labor and without any necessity for careful packing or arrangement which is considered necessary in regular tray acetate distillation. A rotary still of this character also has extremely large capacity in proportion to its floor space and installation cost. A still thirty feet long and eight feet or so in diameter can treat a charge of ten to twelve tons of acetate ma "terial in as short a time as four to six hours,

if desired,and secure a very much higher acetone yield therefrom than is possible with the standard pot or tray stills.

This invention has been described in connection with a number of illustrative forms of apparatus, parts, arrangements, materials. conditions, duration of steps and temperatures, to the details of which disclosure the invention is not of course to be limited, since what is claimed as new and desired to be covered by Letters Patent is set forth in the appended claims:

1. In apparatus for acetate distillation, a rotary horizontally mounted cylindrical metallic retort having hollow axial trunnions, a housing forming an enclosed annular heating chamber in which said retort is mounted, heating means communicating with said chamber and comprising regulated inlet ports beneath the ascending side of the retort and outlet ports in staggered relation to said inlet ports and through which the heating gases escape after traveling around the retort, charging man-holes in said retort and cooperatingicharging and discharge hoppers in said housing, discharge valves in said retort and cooperating bodily movable discharge sleeves arranged to enclose said discharge valves under discharging conditions, inlet and vapor discharge pipes communicating with the interior of said retort and having raised inner ends to minimize entrance of material therein.

2. In apparatus for acetate distillation and so forth, a rota'ry horizontally mounted cylindrical metallic retort, a housing forming a heating chamber in which said retort is mounted, heating means communicating with said chamber to supply heat to said to supply heat to said retort, a discharge 10 opening in said retort and a cooperating movable discharge chute mounted in said housing and means to move said chute into cooperation with said discharge opening. NOEL STATHAM.

Witnesses:

W. L. Covnncr, Geo. PERKINS. 

